1. Field of the Invention
The invention relates to a detection device, and, more particularly, to an ultrasonic phase-shift detection device.
2. Description of Related Art
In the prior art, the state of fluid, such as concentration or velocity of fluid, can be measured by using an ultrasonic flowmeter, which detects the phase shift of the transmitted ultrasonic signals in a fluid. The change of concentration or velocity of fluid may cause the transmitted ultrasonic signals to generate phase shift, and thus the change in concentration or velocity of the fluid can be determined by measuring phase shift of the transmitted ultrasonic signals.
Please refer to FIG. 1, FIG. 1 is a schematic diagram of an ultrasonic flowmeter in the prior art. As shown in FIG. 1, an ultrasonic flowmeter 1 includes a microprocessor 11, a fluid pipe 12, an amplifier 13 and a counter 14. The microprocessor 11 is connected to the fluid pipe 12 and the counter 14. The amplifier 13 is connected to the fluid pipe 12 and the counter 14. The fluid pipe 12 includes a transmitter 121, a receiver 122, an inlet 123 and an outlet 124. The transmitter 121 and the receiver 122 are provided for transmitting and receiving ultrasonic signals respectively, and the inlet 123 and the outlet 124 are provided for fluid to flow in and out respectively. The fluid pipe 12 is filled with the fluid. The microprocessor 11 generates ultrasonic signals and drives the transmitter 121 to transmit the ultrasonic signals, and enables the counter 14 to start counting simultaneously. The receiver 122 sends the received ultrasonic signals to the amplifier 13 for amplification, and enables the counter 14 to stop counting. The counter 14 outputs a digital result signal as the counting result. The above-mentioned procedure of firmware control is quite complicated, and the parameters may need to be modified and corrected very frequently during using. Further, the typical ultrasonic flowmeter should be installed inside the device for fluid measurement during hardware manufacturing. Besides, if an analog signal of measurement result is required, external hardware circuit has to be added for signal conversion.
Therefore, it is desirable to provide an easy-of-use ultrasonic phase-shift detection device capable of outputting both analog and digital measurement results, so as to mitigate and/or obviate the aforementioned problems.